Inequalities

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Inequalities

by ov25 » Mon Dec 13, 2010 7:29 am
If m and n are integers, amd m>0>n, is m^n<1?

i) m is an even number
ii) n^2 > 1

So it appears as though the stem already says it all and there is no need of any more information. Please help!

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by kmittal82 » Mon Dec 13, 2010 7:55 am
I dont think the question stem has all the information.

Consider m = 1 and n = -1 , in which case m ^ n = 1

For any other values of m and n, m ^ n will always be less than 1, but we still need to rule out the possibility of m = 1 and n = -1.

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by ov25 » Mon Dec 13, 2010 8:09 am
So..lets see

1) m>1 SUFF
2) n<-1 INSUFF
1/2^-5 = 2^5 = 32
and 2^-5 = 1/32

A right?

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by kmittal82 » Mon Dec 13, 2010 8:18 am
ov25 wrote:So..lets see

1) m>1 SUFF
2) n<-1 INSUFF
1/2^-5 = 2^5 = 32
and 2^-5 = 1/32

A right?
I think the answer is right, but there is a flaw in your argument.

m cannot be 1/2, since m and n are both integers.

Statement 2 tells us that n is not equal to -1, but it doesnt say anything about m. If m is 1, then n could be anything and the result would be 1, which makes statement 2 insufficient. However, statement 1 says that m is greater than 1, so for any value of n, m ^ n will always be less than 1.